Abstract: Sixteen horses were used to determine if number of trials given per training session (5, 10, 15 or 20) affected learning performance in an avoidance conditioning task. The horse had to move from one side of a test pen to the other during an auditory cue presentation to avoid aversive stimulation. A pen 8 mx3.6 m, divided into two equal sections by a 13-cm diameter plastic pipe lying on the ground, was used as the test pen. Painted plywood panels were fastened to the fence in half the pen to help horses distinguish visually between the two parts. A 10-s auditory cue was used as a signal for horses to move from one side of the test pen to the other. A 20-s intertrial interval was used. Training sessions were conducted every third day. Each trial was recorded as an avoidance (the horse completed the task during auditory cue presentation and avoided aversive stimulus) or an error (the horse received aversive stimulus). After completing ten consecutive avoidances (criterion), the horse was removed from the study. Numbers of training sessions, trials, avoidances and errors until reaching criterion were recorded for each horse. Horses varied greatly within these variables with ranges of 3-18 sessions, 37-121 trials, 20-68 avoidances and 17-53 errors to criterion. No differences were detected (P>0.05) in the number of conditioning trials per training session (treatment) for the mean number of trials, avoidances or errors to criterion. Number of training sessions to criterion differed (P<0.01) among treatments, indicating that an optimum number of learning trials per training session might exist. Mean sessions to criterion for horses receiving 5, 10, 15 and 20 trials per session were 15.1+/-1.3, 5.8+/-1.1, 5.3+/-1.1 and 4.6+/-1.1, respectively. Regression analysis indicated that 16.2 trials per training session would minimize number of sessions to criterion. Although it is widely assumed that learning efficiency in horses is decreased when intense activity is concentrated into a small number of sessions, these results indicate that moderate repetition of training activities is needed for efficient learning.

Abstract: Mortality is high in zoo-housed black rhinoceros (Diceros bicornis), and the reproductive rates of captive white rhinoceros (Ceratotherium simum) are unsustainably low. To determine the possible role of stress in the causation of these problems, we analyzed weekly fecal samples collected for 1 year from black (10 males and 16 females) and white (six males and 13 females) rhinoceroses at 16 zoos for corticoid metabolite concentrations. Fecal corticoid profiles were examined in relation to behavior as rated by keepers in a questionnaire, luteal phase ovarian cycles of females (Brown et al., 2001), and socioenvironmental factors. We compared individual fecal corticoid profiles by examining hormone means and variability (i.e., standard deviation (SD) and coefficient of variation (CV)). For the black rhinos, higher mean corticoid concentrations were found at zoos where rhinos were maintained in enclosures that were exposed to the public around a greater portion of the perimeter. Higher variability in corticoid excretion was correlated with higher rates of fighting between breeding partners and higher institutional mortality rates. Black rhino pairs that were kept separated exhibited lower corticoid variability and less fighting activity when they were introduced during female estrous periods compared to pairs that were kept together every day. For white rhinos, significantly lower mean corticoids were found for individuals that rated higher on “friendliness to keeper.” Higher corticoid variability was found in noncycling as compared to cycling white rhino females. Noncycling females exhibited higher rates of stereotypic pacing and lower frequencies of olfactory behaviors. Interindividual differences in mean corticoids in both species appeared to be related to responsiveness to humans, whereas corticoid variability was related to intraspecific social relationships. More importantly, high corticoid variability appeared to be an indicator of chronic or “bad” stress, because of its association with potentially deleterious consequences in each species (i.e., fighting and mortality (black rhino), and reproductive acyclicity (white rhino)). Our results provide evidence that social stressors may cause chronic stress in black and white rhinos, and that this contributes to the captive-population sustainability problems observed in each species. Zoo Biol 0:1–18, 2005. © 2005 Wiley-Liss, Inc.

Abstract: The work of innovation management involves cross-functional coordination among specialists and managers with different work orientations, time horizons, professional backgrounds, and values (Ford and Randolph, 1992). While strong connections across functions are critical for new product development success (Green et al., 2000), some managers may be more adept at fostering effective cross-functional relationships than others. In this article, the authors empirically examine the factors that distinguish reputationally effective innovation workers from their less effective peers. Drawing on the work of Tsui (1984, 1994), reputational effectiveness is defined as the degree to which a manager has been responsive to the needs and expectations of constituents. This research examines the relational skills and interaction patterns of more (versus less) reputationally effective managers. A large business unit of a Fortune 500 telecommunications firm provided the context for our study. Using a two-phase approach, the authors first captured the social network patterns of 268 managers from marketing, research and development (R&D), manufacturing, and other business functions that were involved in the new product development process. In addition, the reputational effectiveness of each person who was identified as a member of the network was measured. In the second phase, the authors examined the relational competencies (e.g., role-taking ability, interpersonal control, openness) of the managers who participated in Phase I of the research. As predicted, the results indicate that role-taking ability is related positively to a manager's reputational effectiveness. No support, however, was found for the relationship between interpersonal control and reputational effectiveness. Interestingly, the authors found evidence of an inverse relationship between openness and effectiveness. By sharing too much information?or alternatively information that does not relate to the task at hand?the reputational effectiveness of a manager is damaged. Importantly, the results reveal that the social network characteristics of a reputationally effective manager differ from those of less effective managers. Closeness centrality, a measure of the degree of access one has to other organizational members, was associated strongly with reputational effectiveness. The results demonstrate that managers who are successful in working across functions appreciate the cognitive and emotional perspectives of diverse constituents and develop relationship ties that provide them with ready access to others across the organization.